A review is given of water vapor transport features over the Meiyu belt along the Yangtze River valley, the teleconncetion dynamic structure of strong signal forcing sources (Qinghai Tibetan Plateau and tropical oceans) for droughts/floods in the Yangtze River valley, and the water vapor transport source/sink structure related with monsoon Meiyu rainfall. Through synthetic analyses, some results are obtained: The dynamic effect of the Plateau contributes to the long distance water vapor transport, turning at the Plateau from lower latitude oceans to the Yangtze River valley. The oceanic strong signals have influence on the regional drought/flood disastrous climate anomaly. As well, the dynamic mechanisms for two dimensional Rossby wave and low frequency wave energy propagation are explored.